A couple has two children diagnosed with an autosomal dominant genetic disease and asks the healthcare professional what the probability is that their next child will have the same genetic disease. What response by the professional is best?

Question

Quizplus · Accepted Answer

Affected heterozygous individuals transmit the trait to approximately one half of their children; however, because gamete transmission is subject to chance fluctuations, it is possible that all or none of the children of an affected parent may have the trait. Nevertheless, when large numbers of matings of this type are studied, the proportion of affected children closely approaches one half.

A Couple Has Two Children Diagnosed with an Autosomal Dominant